3.0.0

- Add 15 and 16 to Travis
- Updated CHANGELOG.md and README.md
- Removed `GC_MONITORING` as option and `gc-stats` with it

Author: paulrutter

.travis.yml

@@ -8,4 +8,6 @@ node_js:
   - "12"
   - "13"
   - "14"
+  - "15"
+  - "16"
 script: npm run dummy

CHANGELOG.md

@@ -1,3 +1,10 @@
+10-02-2022 Paul Rütter
+- 3.0.0
+- Added Node 16 support (by merging https://github.com/blueconic/node-oom-heapdump/pull/20, Thanks Simon Abbott!).
+  This fixes a recursion issue.
+- Removed "GC_MONITORING" at it relied on `gc-stats`, which is no longer maintained (and contained security issues)
+- Updated `node-pre-gyp` to `@mapbox/node-pre-gyp` so security issues are mitigated
+
 12-10-2020 Paul Rütter
 - 2.1.0
 - Added Node 14 support

README.md

@@ -5,7 +5,7 @@ Node module which will create a V8 heap snapshot right before an "Out of Memory"
 
 It can also create heapdumps and CPU profiles on request like 'v8-profiler', but does this off-process so it doesn't interfere with execution of the main process.
 
-Tested on Node.js 7.x, 8.x, 9.x, 10.x, 11.x, 12.x, 13.x and 14.x.
+Tested on Node.js 7.x, 8.x, 9.x, 10.x, 11.x, 12.x, 13.x, 14.x, 15.x and 16.x.
 No support for Node.js < 7.0 at the moment (although this can be fixed if needed).  
 
 Also comes with prebuilt binaries (hosted on Github releases), thanks to Stuart Miller (https://github.com/spmiller).
@@ -63,17 +63,12 @@ On Node.js 12.x the latter two flags seem to cause some stability issues (see ht
 
 # Options
 * heapdumpOnOOM - boolean whether to create a heapdump when an out of memory occurs. Default true.
-* OOMImplementation - Either "NATIVE_HOOK" or "GC_MONITORING". 
+* OOMImplementation - Only "NATIVE_HOOK" is supported starting from 3.0.0
 "NATIVE_HOOK" relies on the native v8 hook and makes sure that the heapdump is actually created when the OoM occurs. It's more impacted by the OoMKiller of Unix systems though, when being run in memory restricted environments like Docker. 
-"GC_MONITORING" is the old implementation, which relies on GC monitoring. It's less impacted by OoMKiller, because the 'threshold' parameter determines when to create the heapdump. Use this option when you run into the OoMKiller of the Unix OS. Default is "NATIVE_HOOK".
 * path - the path where the heapdump ends up when an out of memory error occurs. '.heapsnapshot' is automatically appended. Defaults to this modules' directory.
 * addTimestamp - add a timestamp to the out of memory heapdump filename, to make it unique. Default is false.
 * port - optionally, the alternative DevTools protocol port. Defaults to 9229. Should map on the port given to the --inspect arg.
 
-The following options are only relevant when OOMImplementation="GC_MONITORING".
-* limit - optionally, specify a limit to how many heapdumps will be created when being above the threshold. Default is 3.
-* threshold - integer between 0 and 100 (%) which determines when to make the heapdump. When the used heapSize exceeds the threshold, a heapdump is made. This value can be tuned depending on your configuration; if memory usage is very volatile, a lower value might make more sense. Default is 70.
-
 # API
 Besides creating heapdumps when an out of memory error occurs, there also is an API for creating heapdumps and CPU profiles on request. See below for the currently available API.
 

index.js

@@ -84,9 +84,8 @@ function parseOptions(options) {
   if (options.heapdumpOnOOM === undefined) {
     options.heapdumpOnOOM = true;
   }
-  if (options.OOMImplementation === undefined){
+  if (options.OOMImplementation === undefined) {
     // default is the "new" implementation
-    // the other option is "GC_MONITORING", which is the old implementation (which is less impacted by OoMKiller)
     options.OOMImplementation = "NATIVE_HOOK";
   }
   if (options.port === undefined) {
@@ -97,16 +96,6 @@ function parseOptions(options) {
   if (options.path === undefined) {
     options.path = "OoM-pid-" + process.pid;
   }
-  if (options.limit === undefined) {
-    options.limit = 3;
-  } else {
-    options.limit = parseInt(options.limit);
-  }
-  if (options.threshold === undefined) {
-    options.threshold = 70;
-  } else {
-    options.threshold = parseInt(options.threshold);
-  }
   if (options.addTimestamp === undefined) {
     options.addTimestamp = false;
   } else {

lib/index.js

@@ -8,48 +8,14 @@ class NodeOomHeapDumpImpl {
     this._files = [];
     this._busy = false;
     this._count = 0;
-    this._limitReached = false;
 
     if (this._opts.heapdumpOnOOM) {
       if (options.OOMImplementation === "NATIVE_HOOK") {
         require('bindings')('node_oom_heapdump_native.node').call(this._getHeapSnapshotPath(this._opts.path), this._opts.addTimestamp);
-      } else if (options.OOMImplementation === "GC_MONITORING") {
-        this._monitorHeap();
       }
     }
   }
 
-  _monitorHeap() {
-    // see https://www.npmjs.com/package/gc-stats	
-    let gcStats = new require('gc-stats')();
-    gcStats.on('stats', (stats) => {
-      // gctype 2 is a Full GC (Mark/Sweep/Compact)	
-      if (stats.gctype === 2 && !this._busy) {
-        let memoryUsagePercentage = Math.round((stats.after.usedHeapSize / stats.after.heapSizeLimit) * 100);
-        if (memoryUsagePercentage > this._opts.threshold) {
-          if (this._count < this._opts.limit) {
-            // this is a full GC and the used heap size is using more than x% of the assigned heap space limit	
-            console.warn('OoM is imminent: Full GC (Mark/Sweep/Compact) complete and still more than %s% (%s%) of the heap is used. Creating heapdump now. GC stats: ', this._opts.threshold, Math.round(memoryUsagePercentage), JSON.stringify(stats));
-
-            this.createHeapSnapshot(this._opts.path, "OoM");
-
-            // block execution of other code for a while (5 second) to enable snapshot to be created	
-            const time = Date.now();
-            let diff = 0;
-            do {
-              diff = Date.now() - time;
-            }
-            while (diff < 5000);
-          } else if (!this._limitReached) {
-            this._limitReached = true;
-            console.warn("OoM heapdump limit reached (%s); no more heapdumps will be created.", this._opts.limit);
-            return;
-          }
-        }
-      }
-    });
-  }
-
 
   /**
    * Calls the designated worker and returns a promise